Multiple projector systems have been developed to project multiple video images to a common display location, such as a screen or wall, to produce a composite display. A composite display is one in which a single image is produced using multiple projectors, with each projector producing a portion or component of the total image. These display systems can be configured to allow multiple sub-frames to overlap completely, not at all, or anything in between, or to provide multiple separate composite images.
One challenge associated with composite images is consistent reproduction of color hue across multiple displays or multiple channels on the same display. For example, color spectra can vary within each individual projector of a composite display system, with the result that the composite image has noticeable irregularities. Knowing the current color properties of each projector is desirable to determine the transformation from a standard color space, such as sRGB, to the device RGB space of the projector, which is used in the calibration of the multiple projector system.
Measurement of primary radiant spectra of each projector has been accomplished using radiographic measurement with an expensive, high-precision instrument such as a spectroradiometer. However, it is often not practical to make high-precision radiographic measurements during the time-constrained setup of a multiple projector display system.